As of August 2009,
this file is mostly complete,
although it is missing some detail on doing a major release (e.g.
5.10.0 -> 5.12.0).
Note that things change at each release,
so there may be new things not covered here,
or tools may need updating.

This document describes the series of tasks required - some automatic,
some manual - to produce a perl release of some description,
be that a snaphot,
release candidate,
or final,
numbered release of maint or blead.

The release process has traditionally been executed by the current pumpking.
Blead releases from 5.11.0 forward are made each month on the 20th by a non-pumpking release engineer.
The release engineer roster and schedule can be found in Porting/release_schedule.pod.

This document both helps as a check-list for the release engineer and is a base for ideas on how the various tasks could be automated or distributed.

The outline of a typical release cycle is as follows:

(5.10.1 is released, and post-release actions have been done)
...time passes...
an occasional snapshot is released, that still identifies itself as
5.10.1
...time passes...
a few weeks before the release, a number of steps are performed,
including bumping the version to 5.10.2
...a few weeks passes...
perl-5.10.2-RC1 is released
perl-5.10.2 is released
post-release actions are performed, including creating new
perl5103delta.pod
... the cycle continues ...

Some of the tasks described below apply to all four types of release of Perl. (snapshot, RC, final release of maint, final release of blead). Some of these tasks apply only to a subset of these release types. If a step does not apply to a given type of release, you will see a notation to that effect at the beginning of the step.

A snapshot is intended to encourage in-depth testing from time-to-time, for example after a key point in the stabilisation of a branch. It requires fewer steps than a full release, and the version number of perl in the tarball will usually be the same as that of the previous release.

A release candidate is an attempt to produce a tarball that is a close as possible to the final release. Indeed, unless critical faults are found during the RC testing, the final release will be identical to the RC barring a few minor fixups (updating the release date in perlhist.pod, removing the RC status from patchlevel.h, etc). If faults are found, then the fixes should be put into a new release candidate, never directly into a final release.

Check that your account is allowed to upload perl distros: goto https://pause.perl.org/, login, then select 'upload file to CPAN'; there should be a "For pumpkings only: Send a CC" tickbox. If not, ask Andreas König to add your ID to the list of people allowed to upload something called perl. You can find Andreas' email address at:

You will need a working git installation, checkout of the perl git repository and perl commit bit. For information about working with perl and git, see pod/perlrepository.pod.

If you are not yet a perl committer, you won't be able to make a release. Have a chat with whichever evil perl porter tried to talk you into the idea in the first place to figure out the best way to resolve the issue.

The work of building a release candidate for a numbered release of perl generally starts several weeks before the first release candidate. Some of the following steps should be done regularly, but all must be done in the run up to a release.

You MAY SKIP this step for SNAPSHOT

Ensure that dual-life CPAN modules are synchronised with CPAN. Basically, run the following:

$ ./perl -Ilib Porting/core-cpan-diff -a -o /tmp/corediffs

to see any inconsistencies between the core and CPAN versions of distros, then fix the core, or cajole CPAN authors as appropriate. See also the -d and -v options for more detail. You'll probably want to use the -c cachedir option to avoid repeated CPAN downloads.

To see which core distro versions differ from the current CPAN versions:

$ ./perl -Ilib Porting/core-cpan-diff -x -a

If you are making a maint release, run core-cpan-diff on both blead and maint, then diff the two outputs. Compare this with what you expect, and if necessary, fix things up. For example, you might think that both blead and maint are synchronised with a particular CPAN module, but one might have some extra changes.

You MAY SKIP this step for SNAPSHOT

Ensure dual-life CPAN modules are stable, which comes down to:

for each module that fails its regression tests on $current
did it fail identically on $previous?
if yes, "SEP" (Somebody Else's Problem)
else work out why it failed (a bisect is useful for this)
attempt to group failure causes
for each failure cause
is that a regression?
if yes, figure out how to fix it
(more code? revert the code that broke it)
else
(presumably) it's relying on something un-or-under-documented
should the existing behaviour stay?
yes - goto "regression"
no - note it in perldelta as a significant bugfix
(also, try to inform the module's author)

You MAY SKIP this step for SNAPSHOT

Similarly, monitor the smoking of core tests, and try to fix.

You MAY SKIP this step for SNAPSHOT

Similarly, monitor the smoking of perl for compiler warnings, and try to fix.

You MAY SKIP this step for SNAPSHOT

Run Porting/cmpVERSION.pl to compare the current source tree with the previous version to check for for modules that have identical version numbers but different contents, e.g.:

then bump the version numbers of any non-dual-life modules that have changed since the previous release, but which still have the old version number. If there is more than one maintenance branch (e.g. 5.8.x, 5.10.x), then compare against both.

Note that some of the files listed may be generated (e.g. copied from ext/ to lib/, or a script like lib/lib_pm.PL is run to produce lib/lib.pm); make sure you edit the correct file!

Once all version numbers have been bumped, re-run the checks.

Then run again without the -x option, to check that dual-life modules are also sensible.

Read Porting/how_to_write_a_perldelta.pod, and try to make sure that every section it lists is, if necessary, populated and complete. Copy edit the whole document.

You MUST SKIP this step for SNAPSHOT

A week or two before the first release candidate, bump the perl version number (e.g. from 5.10.0 to 5.10.1), to allow sufficient time for testing and smoking with the target version built into the perl executable. For subsequent release candidates and the final release, it it not necessary to bump the version further.

There is a tool to semi-automate this process. It works in two stages. First, it generates a list of suggested changes, which you review and edit; then you feed this list back and it applies the edits. So, first scan the source directory looking for likely candidates. The command line arguments are the old and new version numbers, and -s means scan:

i.e. in the file NetWare/Makefile, line 89 would be changed as shown. Review the file carefully, and delete any -/+ line pairs that you don't want changing. You can also edit just the + line to change the suggested replacement text. Remember that this tool is largely just grepping for '5.10.0' or whatever, so it will generate false positives. Be careful not change text like "this was fixed in 5.10.0"! Then run:

$ Porting/bump-perl-version -u < /tmp/scan

which will update all the files shown.

Be particularly careful with INSTALL, which contains a mixture of 5.10.0-type strings, some of which need bumping on every release, and some of which need to be left unchanged. Also note that this tool currently only detects a single substitution per line: so in particular, this line in README.vms needs special handling:

When the version number is bumped, you should also update Module::CoreList (as described below in "Building a release - on the day") to reflect the new version number.

You MUST SKIP this step for SNAPSHOT

Review and update INSTALL to account for the change in version number; in particular, the "Coexistence with earlier versions of perl 5" section.

You MUST SKIP this step for SNAPSHOT

Update the Changes file to contain the git log command which would show all the changes in this release. You will need assume the existence of a not-yet created tag for the forthcoming release; e.g.

git log ... perl-5.10.0..perl-5.12.0

Due to warts in the perforce-to-git migration, some branches require extra exclusions to avoid other branches being pulled in. Make sure you have the correct incantation: replace the not-yet-created tag with HEAD and see if git log produces roughly the right number of commits across roughly the right time period (you may find git log --pretty=oneline | wc useful).

Check some more build configurations. The check that setuid builds and installs is for < 5.11.0 only.

Re-read the perldelta to try to find any embarrassing typos and thinkos; remove any TODO or XXX flags; update the "Known Problems" section with any serious issues for which fixes are not going to happen now; and run through pod and spell checkers, e.g.

If not already built, Configure and build perl so that you have a Makefile and porting tools:

$ ./Configure -Dusedevel -des && make

Check that files managed by regen.pl and friends are up to date. From within your working directory:

$ git status
$ make regen
$ make regen_perly
$ git status

If any of the files managed by regen.pl have changed, then you should re-make perl to check that it's okay, then commit the updated versions:

$ git commit -a -m 'make regen; make regen_perly'

Rebuild META.yml:

$ rm META.yml
$ make META.yml
$ git diff

XXX it would be nice to make Porting/makemeta use regen_lib.pl to get the same 'update the file if its changed' functionality we get with 'make regen' etc.

Commit META.yml if it has changed:

$ git commit -m 'Update META.yml' META.yml

You MUST SKIP this step for SNAPSHOT

Update Module::Corelist with module version data for the new release.

Note that if this is a maint release, you should run the following actions from the maint directory, but commit the Corelist.pm changes in blead and subsequently cherry-pick it.

corelist.pl uses ftp.funet.fi to verify information about dual-lived modules on CPAN. It can use a full, local CPAN mirror or fall back to wget or curl to fetch only package metadata remotely. (If you're on Win32, then installing Cygwin is one way to have commands like wget and curl available.)

If this not the first update for this version (e.g. if it was updated when the version number was originally bumped), first edit dist/Module-CoreList/lib/Module/CoreList.pm to delete the existing entries for this version from the %released and %version hashes: they will have a key like 5.010001 for 5.10.1.

XXX the edit-in-place functionality of Porting/corelist.pl should be fixed to handle this automatically.

Then, If you have a local CPAN mirror, run:

$ ./perl -Ilib Porting/corelist.pl ~/my-cpan-mirror

Otherwise, run:

$ ./perl -Ilib Porting/corelist.pl cpan

This will chug for a while, possibly reporting various warnings about badly-indexed CPAN modules unrelated to the modules actually in core. Assuming all goes well, it will update dist/Module-CoreList/lib/Module/CoreList.pm.

Check that file over carefully:

$ git diff dist/Module-CoreList/lib/Module/CoreList.pm

If necessary, bump $VERSION (there's no need to do this for every RC; in RC1, bump the version to a new clean number that will appear in the final release, and leave as-is for the later RCs and final).

Edit the version number in the new 'Module::CoreList' => 'X.YZ' entry, as that is likely to reflect the previous version number.

Also edit Module::CoreList's new version number in its Changes file and in its META.yml file.

In addition, if this is a final release (rather than a release candidate):

Update this version's entry in the %released hash with today's date.

Make sure that the script has correctly updated the CAVEATS section

Finally, commit the new version of Module::CoreList: (unless this is for maint; in which case commit it blead first, then cherry-pick it back).

Make sure that the correct pumpking is listed in the left-hand column, and if this is the first release under the stewardship of a new pumpking, make sure that his or her name is listed in the section entitled THE KEEPERS OF THE PUMPKIN.

Be sure to commit your changes:

$ git commit -m 'add new release to perlhist' pod/perlhist.pod

You MUST SKIP this step for SNAPSHOT

Update patchlevel.h to add a -RC1-or-whatever string; or, if this is a final release, remove it. For example:

Check that the output of /tmp/perl-5.x.y-pretest/bin/perl -v and /tmp/perl-5.x.y-pretest/bin/perl -V are as expected, especially as regards version numbers, patch and/or RC levels, and @INC paths. Note that as they have been been built from a git working directory, they will still identify themselves using git tags and commits.

Then delete the temporary installation.

If this is maint release, make sure Porting/mergelog is saved and committed.

Push all your recent commits:

$ git push origin ....

You MUST SKIP this step for SNAPSHOT

Tag the release (e.g.):

$ git tag v5.11.0 -m'First release of the v5.11 series!'

(Adjust the syntax appropriately if you're working on Win32, i.e. use -m "..." rather than -m'...'.)

It is VERY important that from this point forward, you not push your git changes to the Perl master repository. If anything goes wrong before you publish your newly-created tag, you can delete and recreate it. Once you push your tag, we're stuck with it and you'll need to use a new version number for your release.

Create a tarball. Use the -s option to specify a suitable suffix for the tarball and directory name:

This creates the directory ../perl-x.y.z-RC1 or similar, copies all the MANIFEST files into it, sets the correct permissions on them, adds DOS line endings to some, then tars it up as ../perl-x.y.z-RC1.tar.gz. With -b, it also creates a tar.bz2 file.

XXX if we go for extra tags and branches stuff, then add the extra details here

Clean up the temporary directory, e.g.

$ rm -rf ../perl-x.y.z-RC1

Copy the tarballs (.gz and possibly .bz2) to a web server somewhere you have access to.

Download the tarball to some other machine. For a release candidate, you really want to test your tarball on two or more different platforms and architectures. The #p5p IRC channel on irc.perl.org is a good place to find willing victims.

Check that the output of perl -v and perl -V are as expected, especially as regards version numbers, patch and/or RC levels, and @INC paths.

Note that the results may be different without a .git/ directory, which is why you should test from the tarball.

Run the Installation Verification Procedure utility:

$ bin/perlivp
...
All tests successful.
$

Compare the pathnames of all installed files with those of the previous release (i.e. against the last installed tarball on this branch which you have previously verified using this same procedure). In particular, look for files in the wrong place, or files no longer included which should be. For example, suppose the about-to-be-released version is 5.10.1 and the previous is 5.10.0:

(Use ... -e "shell" instead on Win32. You probably also need a set of Unix command-line tools available for CPAN to function correctly without Perl alternatives like LWP installed. Cygwin is an obvious choice.)

Try installing a popular CPAN module that's reasonably complex and that has dependencies; for example:

(Again, on Win32 you'll need something like Cygwin installed, but make sure that you don't end up with its various bin/cpan* programs being found on the PATH before those of the Perl that you're trying to test.)

and carefully examine the output (in perlbug.rep]), especially the "Locally applied patches" section. If everything appears okay, then delete the file, and try it again, this time actually submitting the bug report. Check that it shows up, then remember to close it!

Wait for the smoke tests to catch up with the commit which this release is based on (or at least the last commit of any consequence).

Then check that the smoke tests pass (particularly on Win32). If not, go back and fix things.

Once smoking is okay, upload it to PAUSE. This is the point of no return. If anything goes wrong after this point, you will need to re-prepare a new release with a new minor version or RC number.

If your workstation is not connected to a high-bandwidth, high-reliability connection to the Internet, you should probably use the "GET URL" feature (rather than "HTTP UPLOAD") to have PAUSE retrieve the new release from wherever you put it for testers to find it. This will eliminate anxious gnashing of teeth while you wait to see if your 15 megabyte HTTP upload successfully completes across your slow, twitchy cable modem. You can make use of your home directory on dromedary for this purpose: http://users.perl5.git.perl.org/~USERNAME maps to /home/USERNAME/public_html, where USERNAME is your login account on dromedary. Remember: if your upload is partially successful, you may need to contact a PAUSE administrator or even bump the version of perl.

Upload both the .gz and .bz2 versions of the tarball.

Wait until you receive notification emails from the PAUSE indexer confirming that your uploads have been successfully indexed. Do not proceed any further until you are sure that the indexing of your uploads has been successful.

Now that you've shipped the new perl release to PAUSE, it's time to publish the tag you created earlier to the public git repo (e.g.):

Then manually edit (vms/descrip_mms.template to bump the version in the following entry:

[.pod]perldelta.pod : [.pod]perl5101delta.pod

XXX this previous step needs to fixed to automate it in pod/buildtoc.

Manually update references to the perlNNNdelta version in these files:

INSTALL
README

Edit the previous delta file to change the NAME from perldelta to perlNNNdelta.

These two lists of files probably aren't exhaustive; do a recursive grep on the previous filename to look for suitable candidates that may have been missed.

Finally, commit:

$ git commit -a -m 'create perlXXXdelta'

At this point you may want to compare the commit with a previous bump to see if they look similar. See commit ca8de22071 for an example of a previous version bump.

You MUST SKIP this step for RC, BLEAD

If this was a maint release, then edit Porting/mergelog to change all the d (deferred) flags to . (needs review).

You MUST SKIP this step for RC, BLEAD

If this was the first release of a new maint series, (5.x.0 where x is even), then create a new maint branch based on the commit tagged as the current release and bump the version in the blead branch in git, e.g. 5.12.0 to 5.13.0.